Managing patient information can be particularly difficult when serving complex patients who have multiple physical, mental, and social needs, and are often seen by multiple health care professionals. When coordinating care for such patients, primary care clinicians and their staff must locate, obtain, and synthesize the wide range of information needed to assess patients, make clinical decisions, monitor progress, and identify care goals. They also must identify the people involved in the patient's care, and share information effectively, even with members of the care team located in other settings. Health information technology (health IT) that optimally supports the information access, management, and sharing required for effective care coordination is critical to addressing this complicated set of information needs. Yet while health IT tools - especially electronic health records (EHRs) - are becoming common in primary care practice, such tools are rarely designed specifically to address primary care teams' information management needs in the context of providing and coordinating care for complex patients. As a result, such IT systems can actually perpetuate care fragmentation, inefficiencies, and workarounds leading to errors and lower quality care. We focus on identifying the clinically relevant information that clinicians and clinical teams commonly need when caring for complex patient populations, and examine how clinical teams use health IT to address the social and economic circumstances that are often central to their complex patients' health and healthcare (known as social determinants of health). We identify the information needs that must be met to ensure effective care coordination for complex patients through extensive ethnographic assessment and interviews, and employ state-of-the-art user-centered design methods to rapidly develop and test health IT tools that address these needs. This work will be conducted in partnership with OCHIN, Inc., a non-profit organization nationally recognized for its health IT innovations, and its large network of Community Health Centers (CHCs). Through this partnership, we will undertake the following specific aims: Aim 1: Identify CHC clinicians' and clinical teams' information needs when they work individually and collaboratively to coordinate care for complex patients; Aim 2: Identify CHC clinicians' and clinical teams' information needs regarding patients' social determinants of health, and methods for obtaining this information and integrating it into the EHR so as to inform clinical decision-making when caring for complex patients; and Aim 3: Identify design principles; use proven development methods to rapidly develop and test health IT tools to meet the health IT needs identified in Aims 1 and 2. Our study population will include clinicians and staff at 10 CHCs. This study will provide a set of practice and actionable design principles that will be widely disseminated, and health IT tools that demonstrate these principles and will be ready for implementation in the OCHIN network and among other EHR users.